Ang told Mr Go to stop the taxi at a bus stop along Ang Mo Kio Avenue 1 and became angry when he heard the older man's reply to his query about the fare.

He scolded the driver who alighted as he felt afraid.

Deputy Public Prosecutor Sarah Ong said: "The accused also alighted from the taxi and aggressively walked over to confront the victim... As the victim felt threatened by the accused, the victim pushed the accused away but the accused nevertheless managed to punch the victim's mouth."

Ang chased after Mr Go when he tried to run away and punched the back of his head, causing him to fall to the ground.

Ang refused to let Mr Go get away when he managed to get up and continued to chase him around the taxi.

DPP Ong added: "While doing so, the accused cursed, shouted and gestured aggressively at the victim... At several points, the accused's girlfriend grabbed the accused's arm and held him back as he followed the victim around the taxi."

After some time, Mr Go managed to get hold of his mobile phone from the driver's seat and called for the police.

Despite this, Ang still refused to back down and continued to pursue him around the vehicle.

Officers soon arrived at the scene and Mr Go was taken to Tan Tock Seng Hospital.

He was found with injuries including a swollen lower lip and was given four days of hospitalisation leave.

DPP Ang asked District Judge Kan Shuk Weng to jail Ang for at least six weeks, stressing that he originally wanted to claim trial.

His lawyer, Ms Sherrie Chong, who was assigned to the case under the Criminal Legal Aid Scheme, asked for a sentence of not more than four weeks. She also said that Mr Go had pushed her client.

For causing hurt, Ang could have been jailed up to two years and fined up to $5,000.